1500W Zener TVS — the protection envelope
The 1.5SMC56A M6G: That 1500W rating is the headline selection parameter — it tells you how much transient energy the part can absorb before the junction gives way. For a 47.8V reverse standoff voltage, the clamp voltage peaks at 77V at the rated 20A peak pulse current, so the protected rail sees a hard ceiling at 77V during a surge event.
DO-214AB — standard TVS footprint
The footprint is shared across the 1.5SMC family, so swapping between voltage variants on the same PCB land pattern is straightforward — the same copper pad handles the 1500W dissipation. No power line protection feature here (the part is a standalone transient suppressor, not a filtered combo device).